The ability is never named in-game, but it is the ability of the Celestriad relic (called Economizer in the original version). This relic makes all magic spells, lores, and summons cost 1 MP. A simple way to acquire a Celestriad that requires a little patience is to bet a Murakumo at Dragon's Neck Coliseum and fight the battle with Gogo giving him three Steal commands, a Safety Bit and a Brigand's Glove. With Gogo stealing from the Galypdes there is a 1/8 chance of stealing a Celestriad. The Murakumo yields a Holy Lance that can be bet to get the Murakumo back, for repeated attempts.